An endoscopic access device is typically a flexible tube inserted into a patient through a natural opening or a percutaneous incision to visualize and perform certain procedures. From time to time, various medical devices such as snares, pincers, morcellators, forceps, scopes, or baskets are introduced through the proximal opening of the endoscopic device to perform medical procedures inside a patient's body. Moreover, light sources, cameras, and other scopes may also be introduced through the endoscopic device from time to time to illuminate organs, capture images, or view organ properties.
Often, in minimally invasive surgery, laser devices are used to cauterize, fragment, or excise tissue and/or other masses within a patient's body. The laser is introduced through the endoscopic device once the device has been positioned proximal a desired surgical site. The laser fiber tip is extended from the distal end of the endoscopic device and then fired. Sometimes, however, it is difficult to determine the laser's exact position with respect to the endoscopic device. Thus, it is likely that the laser might fire while it is still inside the endoscopic device, potentially damaging the instrument. Moreover, during operations, the laser device may inadvertently be displaced, pushing the laser tip back into the endoscopic device tube while the laser is still functioning, potentially damaging the endoscopic device.
In recent years, one major repair cost incurred by endoscopic operators stems from lasers misfiring during procedures. In an attempt to prevent the laser from firing at the wrong time, a recent technique captures images of the laser head using a camera located at the endoscopic device's distal tip. The laser head is fired only when the operator can see the laser head protruding from the endoscopic device. Though this technique can solve the problem, it adds overhead and size—the camera and associated electronics. In most minimally invasive procedures, space is a major constraint. For example, in cholangioscopy, the endoscopic device is inserted through a small urethral opening, requiring a very small endoscopic device. Scientists continuously work towards inventing devices that are small enough to fit in these tiny spaces. Adding a space requirement for a camera merely to determine the position of the laser device reduces the space available for other devices and increases cost.
Therefore, there exists the need for a laser position detection system that does not utilize much space in the working channel and still helps prevent laser misfiring.